In 1881, Frederick Douglass published a revised version of his autobiography, the Life and Times of Frederick Douglass. In it, he was very critical of Robert C. Winthrop's role during the Civil War, but in this March 1882 letter to Winthrop's son, Robert C. Winthrop, Jr., Douglass apologizes for the "injustice" he had done to the elder Winthrop's reputation, and promised to "redress this wrong" in future editions of his Life and Times.

In his memoirs, Douglass recollected that in 1865, he had shared a speaking platform at Faneuil Hall in Boston with Winthrop to celebrate the capture of Richmond and the collapse of the Confederacy. Douglass wrote scornfully of Winthrop's late "conversion" to the Union cause during the Civil War. He compared the "aristocratic" Winthrop, a former speaker of the house and senator in the United Sates Congress, unfavorably to the late Henry Wilson, a rough-hewn shoemaker who had risen up to represent Massachusetts in the senate and who died in office as vice president of the United States. Douglass reflected that while:

Regiment after regiment, brigade after brigade, had passed over Boston Common to endure the perils and hardships of war... a word from Winthrop [a celebrated public speaker] would have gone far to nerve up those young soldiers going forth to lay down their lives for the life of the republic; [but] no word came. Yet now, in the last quarter of the eleventh hour, when the day's work was near done, Robert C. Winthrop was seen standing upon the same platform with the veteran Henry Wilson.

Unfortunately, Douglass' opinion of Winthrop had been shaped by the latter's opposition to the anti-slavery movement and his support for George B. McClellan in the 1864 presidential election, rather than Winthrop's actual role as a strong supporter of the Union cause. In fact, Winthrop had done exactly what Douglass accused him of not doing; he had delivered speeches when Massachusetts regiments received their colors or departed for the front.

As the letter indicates, an examination of Winthrop's published speeches made this point clear and Douglass, true to his word, revised his text, first by adding a chapter note apologizing for his mischaracterization of Winthrop, and later by substantially modifying--reversing--his description of Winthrop's role during the Civil War in later editions of his Life and Times:

For, when the Union needed him, and all others, as the slaveholding rebellion was raising its defiant head...the beloved Winthrop, the proud representative of what Daniel Webster once called the "solid men of Boston," showed that he was not prepared to sacrifice his patriotism to party. He made the loyal cause his own.

Douglass did retain an ironic anecdote about how, twenty-five years before they spoke together in Boston, during Douglass' fugitive slave days in New Bedford, he had been a waiter at a dinner for Winthrop. In his diary, Winthrop recorded his impression of the 1865 Faneuil Hall program: while he did not believe that he had ever seen Douglass before, he thought that Douglass had done well. "It was an odd company for me," the conservative Winthrop wrote, "but I can rejoice at the success of Union arms in any company."